1. Field of the Invention
The present invention relates to interconnection technology and, in particular, to a ceramic body having a dispersion of conductive particles therein which, upon application of a predetermined electrical potential, form continuous electrical conduction paths through the material of the ceramic body.
2. Description of the Prior Art
As the density and complexity of integrated circuits increase a limiting factor has been found to exist in the ability to interconnect signals emanating from a given integrated circuit to other devices. See, Electronics, April 1989, p.106. Present solutions to this interconnectability problem have evolved to the use of multilayer ceramic interconnecting structures.
Conductive tracings fired onto the surface of an insulating ceramic body define patterns of interconnection lines whereby a given integrated circuit may be electrically connected to other devices. The patterns of conductive materials are formed on a ceramic material layer using photolithography or silkscreen technology. The ceramic material may be made via thick film ("green tape") ceramic technology. Several such ceramic layers are laminated together to form a complex circuit, with connections between layers provided by "vias" (holes filled with metal). The top ceramic layer also provides bonding pads on which the chips are mounted. Suitable thick-film materials for such interconnects are manufactured and sold by the Electronic Materials Division of Electronics Department of E. I. du Pont de Nemours & Co. A similar process can be used with thin-film ceramic technology, and laminates with over thirty-two (32) layers have been made using such technology.
Alternative interconnection structures are also known. For example, U.S. Pat. No. 4,359,414, issued to Mastrangelo and assigned to the assignee of the present invention, discloses an insulating flexible polymeric film having metal particles dispersed therein. Upon application of a predetermined potential electrical breakdown occurs activating the particles to form a continuous electrical conduction path through the film. Such polymer-based compositions provide programmable electrical interconnections, but those materials may start to degrade at high temperatures.